gcc4.0 recent >15% runtime performance regression

Uros Bizjak uros@kss-loka.si
Mon Jan 3 07:32:00 GMT 2005


Hello!

>gcc-4.0-20050102
>  4010d4:       movss  (%ecx,%esi,4),%xmm0
>  4010d9:       movss  %xmm0,0x4(%esp)
>  4010df:       movaps %xmm0,%xmm1
>  4010e2:       movaps %xmm2,%xmm0
>  4010e5:       flds   (%edx,%ebx,4)
>  4010e8:       mulss  %xmm3,%xmm1
>  4010ec:       movss  (%edx,%esi,4),%xmm4
>  4010f1:       fsubrs 0xc(%edi)
>  4010f4:       mulss  %xmm4,%xmm3
>  4010f8:       movss  (%edx,%eax,4),%xmm5
>  4010fd:       movss  (%ecx,%eax,4),%xmm7
>  401102:       addss  (%ecx,%ebx,4),%xmm1
>  401107:       mulss  %xmm5,%xmm2
>  40110b:       mulss  %xmm7,%xmm0
>  40110f:       fstps  (%esp)
>  401112:       movss  (%esp),%xmm6
>  401117:       addss  %xmm0,%xmm1
>  40111b:       subss  %xmm3,%xmm6
>  40111f:       xorps  %xmm3,%xmm3
>
Which -mfpmath= option did you use to produce above code?

Uros.



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